There is a reasonable backlog at this point, and it will be a couple of weeks before our resellers have DC8 bundled w/ Jrs. in stock. You'll have to contact Premium to find out about their return policy.
Note that the configuration you have you will actually be able to control more high power devices than you will with the DC8. 2 DC4s is 20 amps total (on two circuits potentially), and with the DC8 it is all on 1 circuit and limited to 15 Amps. For smaller systems it might not matter but for larger systems the internal fuse in the DC8 may blow.
Curt